Field of the Invention
The present invention relates to a hand of a robot arm for transferring a semiconductor wafer.
Description of the Related Art
In semiconductor manufacturing processes, a substrate transfer apparatus is used to transfer semiconductor wafers between processing apparatuses. This substrate transfer apparatus includes a robot arm, and a hand at the distal end of the robot arm supports a wafer (Japanese Patent Laid-Open No. 2001-223252 and Japanese Patent Nos. 4038653, 4740188, and 5548163).
A wafer sometimes deforms as a result of processing. For example, a wafer sometimes warps or bends due to the influence of heat in a heating process. If a wafer has deformed, the wafer may be damaged or misaligned because the hand and the wafer come in contact with each other in an unexpected portion. Therefore, structures in which frictional holding members made of rubber or the like are formed on a hand member forming a hand main body have been proposed (Japanese Patent Laid-Open No. 2001-223252 and Japanese Patent Nos. 4038653 and 4740188).
The frictional holding members are expendables, so their replacement is desirably easy.